Most Complete Tyrannosaur Fossil Discovered In Utah

The dinosaur skeleton is the most complete of its kind found in the Southwest United States. Credit: Mark Johnston/NHMU

After excavation, the dinosaur remains were airlifted by helicopter and taken to the museum for further study

Researchers have unearthed what is being described as the most complete tyrannosaur skeleton found in Southern Utah. The fossil is approximately 76 million years old and belongs to Teratophoneus curriei, a species that roamed the Earth during the Late Cretaceous Period.

“With at least 75 percent of its bones preserved, this is the most complete skeleton of a tyrannosaur ever discovered in the southwestern US. We are eager to get a closer look at this fossil to learn more about the southern tyrannosaur’s anatomy, biology and evolution." Dr. Randall Irmis, a curator at Natural History Museum of Utah said in a statment.

he skeleton is nearly complete, leading scientists to believe the dinosaur was buried either in a river channel or swept into the site by flooding. Its underwater burial kept almost the entire skeleton intact and preserved it in exquisite detail.

The remains of the tyrannosaur were discovered in Kaiparowits Formation, which is already known for yielding fossils of several prehistoric animals.

“The monument is a complex mix of topography—from high desert to badlands—and most of the surface area is exposed rock, making it rich grounds for new discoveries,” said Bureau of Land Management's Grand Staircase-Escalante National Monument Paleontologist Dr. Alan Titus, who discovered the fossil in 201 . "And we're not just finding dinosaurs, but also crocodiles, turtles, mammals, amphibians, fish, invertebrates, and plant fossils—remains of a unique ecosystem not found anywhere else in the world," said Titus.

The specimen was found to be approximately 17-20 feet long with a relatively short head. This is unlike the typically longer-snouted tyrannosaurs previously found in the region. Remarkably, all the dinosaur fossils recovered in the formation appear to be unique to this area and are not found anywhere else on Earth.

Colleting such fossils are however no easy task. They are often found in the areas that are hard to access.

"Many areas are so remote that often we need to have supplies dropped in and the crew hikes in.” Irmis said.

For this particular tyrannosaur fossil, researchers had to work at the site with tools. After three-week of excavation in early May 2017, the fossil remains were recovered and airlifted by helicopter. Then, the dinosaur fossil was taken to the museum for further research and analysis.

“We’ll look at the size of this new fossil, its growth pattern, biology, reconstruct muscles to see how the animal moved, how fast could it run, and how it fed with its jaws,” said Irmis. “The possibilities are endless and exciting.”